code: def test_unique_radiobuttons(self):
      # check that radiobuttons are unique across instances (bpo25684)
      items = ("a", "b", "c")
      default = "a"
      optmenu = ttk.OptionMenu(self.root, self.textvar, default, *items)
      textvar2 = tkinter.StringVar(self.root)
      optmenu2 = ttk.OptionMenu(self.root, textvar2, default, *items)
      optmenu.pack()
      optmenu2.pack()
      optmenu["menu"].invoke(1)
      optmenu2["menu"].invoke(2)
      optmenu_stringvar_name = optmenu["menu"].entrycget(0, "variable")
      optmenu2_stringvar_name = optmenu2["menu"].entrycget(
          0, "variable"
      )
      self.assertNotEqual(
          optmenu_stringvar_name, optmenu2_stringvar_name
      )
      self.assertEqual(
          self.root.tk.globalgetvar(optmenu_stringvar_name), items[1]
      )
      self.assertEqual(
          self.root.tk.globalgetvar(optmenu2_stringvar_name), items[2]
      )
  
      optmenu.destroy()
      optmenu2.destroy()
  
imports: import sys
  import unittest
  import tkinter
  from tkinter import ttk
  from test.support import requires, gc_collect
  from test.test_tkinter.support import AbstractTkTest, AbstractDefaultRootTest
label_desc: Use image node_id 6 for calling the OptionMenuTest obj's underlying member method code with example usage: obj.test_unique_radiobuttons() without return types